In low light,Up to what ISO you willing to go?When handheld at 28mm, how low is shutter speed you willing to go?which camera you refer to?

Mine:200010th-20thG12

Thanks in advance.

Background:

I got 6D recently, coming from a G12 I was carried away, use Av Mode and set aperture < 2.8, ISO range up to 25600. After Christmas, I checked my pictures and a lot of the shots was in 12800 above. And my G12 old pics looks better, in the past I used manual mode on G12 and carefully not go > 1600 ISO and < 1/30 shutter speed.

I mean, it's going to change a lot by camera body. I have a 7d so I hate going above 1600. Really I try to avoid much over 800, but in low light that can be difficult to avoid. If I had a 5d3, just from looking at comparison charts, I'm guessing I'd be willing to go to 6400 in most cases.

Shutter speed at 28mm is most limited by subject motion. I can handhold 1/30 pretty easily if people aren't moving around, but realistically with candids we're talking 1/125, sports 1/250 or as fast as I can afford given the light

I shoot mostly with a 60D. I have shot handheld right up to limit of the extended range of the camera (iso12800) at a 30th of a second with a 100L at f2.8..... if that's what you need to do, do it! Far better than to let the picture escape...... and yes, the picture would have less noise with a newer and better camera, but the picture would not have been as nice.

A lot of these things are guidelines... like never shoot slower than 1/focal length, but guidelines are not hard set laws and sometimes the result of breaking them is a great picture.

I used my 5D MK III up to 25600 the other night at a local play, and that was with fast primes. You do lose lots of image detail, and you will not win any awards for quality, but up to 8X10, it looks fine.

There were some that I just could not capture, since I was at 1/20 sec f/1.8 on my 85mm 1.8 lens, and motion blur was bad.

Fortunately, only a handful required 25600.

Obviously, I would not chose to use high ISO's like that if it wasn't required. Flash is not allowed, and would ruin the liighting. So fast primes, marginal shutter speeds, and high ISO is sometimes the only choice.ISO 25600:

I shoot my 7D at 800 for good shots where I can accept maybe a little motion blur, 1600 where i'd rather have noise than motion blur (noise is easier to get rid of), and 3200 or even higher if it's only going to be a 6x9cm print or 1200x800 web-view.

My EOS 3 I shoot up to 800, which is either BW400CN or TMAX400 pushed a stop, or occasionally when I'm shooting Provia 400 and cross processing, then I set the light-meter to 800 to not blow out the highlights.

And my Pentacon6/Kiev60/Kiev88/Mamiya645AF I shoot Ilford Delta P3200, have shot at 3200 and 4000, and frankly i get better results (less grain than noise) than on my 7D at the same speeds, reducing those huge negatives masks a lot of the grain out. It's hard to compare when my fastest MF lenses are f/2.8, but i'll take my EF 85/1.8 at iso800 on my 7D over the Zeiss Sonnar 180/2.8 at iso3200 on MF (it's also 3kg lighter that way).

No limit as such and I've been known to go all the way to the dizzying heights of 3200 (my 1Ds Mkii's limit). But 90%+ of the time, I'm at ISO 100 and I rarely go above 400 or 800. Interestingly, though, I've started playing around with night time timelapse photography and have been pleasantly surprised how well ISO 1600 works for this.

On 18mp aps-c: Max iso800 for 100% crop usability, maybe iso1250 if I know I don't have to raise shadows in postprocessing and keeper rate would be too low otherwise.

Anything higher imho is only usable if the shots are downsized (which they aften are), that's why I want a 6d, even though higher iso capability doesn't mean more dynamic range at high iso than older sensors...

This may sound simplistic but the ISO choice for me is the minimum to get the job done.

Getting the job means getting a non blurred photo of the subject in the light. ISO selection may be very high but if that is what the photo requires, that is what I put. I cant not take a picture just because it requires higher ISO than what I find pleasing.

If me or my client is picky about the noise then I need to get wider opening lenses and cameras with high ISO capabilities. Even then lowest ISO principle applies.